Multiple Fields for Prefix in ElasticSearch and auto From and Size limit

Question

I got 2 questions related to ElasticSearch.

1) First Question, I have this query with prefix

"must": [
        {
           "prefix": {
              "user": "John"
           }
        }
     ]

with this query, I can Prefix John with User field so it results those documents in which John is found in User field. Now how can I make this query to see if John is prefixed in either any of User or email fields.

---

2) Second Question, I know we can apply Size and from in ElasticSearch to limit Result but I want to know that do I have to explicitly provide Size and from every time I query in ElasticSearch to continue last result or is there any other way to let the ElasticSearch do it for me that I just query and it will give results in a series left from previous.

Answer 1

First, note that the prefix-query does not do any text analysis, so you will not be matching e.g. john with your query.

You should look into the multi_match-query which takes the options of the match-query as well. Thus, you can combine multi_match with phrase_prefix and get the best of both: matching on multiple fields, and text analysis.

Here is a runnable example you can play with: https://www.found.no/play/gist/8197442

#!/bin/bash

export ELASTICSEARCH_ENDPOINT="http://localhost:9200"

# Index documents
curl -XPOST "$ELASTICSEARCH_ENDPOINT/_bulk?refresh=true" -d '
{"index":{"_index":"play","_type":"type"}}
{"user":"John Smith","email":"john.smith@gmail.com"}
{"index":{"_index":"play","_type":"type"}}
{"user":"Alice Smith","email":"john.smith@gmail.com"}
'

# Do searches

curl -XPOST "$ELASTICSEARCH_ENDPOINT/_search?pretty" -d '
{
    "query": {
        "multi_match": {
            "fields": [
                "user",
                "email"
            ],
            "query": "john",
            "operator": "and",
            "type": "phrase_prefix"
        }
    }
}
'

For your second question, look into the scroll API.